Hydroforming is a cost-effective method of shaping ductile metals such as aluminum, brass, low alloy steels, and stainless steel into lightweight, structurally stiff and strong pieces. Hydroforming is widely used in the automotive industry for making complex shapes that are made possible by the hydroforming process to produce stronger, lighter, and more rigid unibody structures for vehicles, as well as in the shaping of aluminum tubes for bicycle frames. Hydroforming is a specialized type of die forming that uses a high pressure hydraulic fluid to press room temperature working material into a die. In order to hydroform aluminum into a vehicle's frame rail, a hollow tube of aluminum is placed inside a negative mold that has the shape of the desired result. High pressure hydraulic pumps inject fluid at very high pressure inside the aluminum, which causes the aluminum to expand until it matches the mold. The hydroformed aluminum is then removed from the mold. Hydroforming allows complex shapes with concavities to be formed, which would be difficult or impossible with standard solid die stamping. Hydroformed parts can often be made with a higher stiffness-to-weight ratio and at a lower per unit cost than traditional stamped or stamped and welded parts. Virtually all metals capable of cold forming can be hydroformed, including aluminum, brass, carbon and stainless steel, copper, and high strength alloys.
The design of the front end architecture of a vehicle is often influenced by assembly requirements for engine installation, and the vehicle's cooling system module. Furthermore, installation clearances for the front bumper often require splitting the lower bar radiator support away from the bolster, which may require a roll form stamping of the lower bar to meet structural requirements.
Thus, there exists a need for front end load bearing bolsters with improved structural performance and lower component weight, while also minimizing material, tooling, and production costs.